package com.longe.netty.http;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.SimpleChannelInboundHandler;
import io.netty.handler.codec.http.*;
import io.netty.util.CharsetUtil;

import java.net.URI;

/**
 * 1. SimpleChannelInboundHandler 是 ChannelInboundHandlerAdapter 的子类
 * 2. HttpObject 客户端和服务器端相互通讯的数据被封装成 HttpObject
 */
public class NettyHttpServerHandler extends SimpleChannelInboundHandler<HttpObject> {

    /**
     * 读取客户端数据
     * @param ctx 上下文
     * @param msg 客户端传递信息
     */
    @Override
    protected void channelRead0(ChannelHandlerContext ctx, HttpObject msg) throws Exception {

        //判断 msg 是不是 httpRequest请求
        if (msg instanceof HttpRequest) {

            System.err.println("ctx 类型: " + ctx.getClass());
            System.err.println("msg 类型: " + msg.getClass());
            System.err.println("客户端地址: " + ctx.channel().remoteAddress());

            //获取到HttpRequest
            HttpRequest httpRequest = (HttpRequest) msg;
            //获取uri, 过滤指定的资源
            URI uri = new URI(httpRequest.uri());
            System.err.println("请求的地址为：" + uri.getPath());
            if ("/favicon.ico".equals(uri.getPath())) {
                System.err.println("请求了 favicon.ico, 不做响应");
                return;
            }
            //回复信息给浏览器 [http协议]
            ByteBuf content = Unpooled.copiedBuffer("老司机, 我是服务器", CharsetUtil.UTF_8);

            //构造一个http的响应, 即 httpResponse
            FullHttpResponse response = new DefaultFullHttpResponse(HttpVersion.HTTP_1_1, HttpResponseStatus.OK, content);
            response.headers().set(HttpHeaderNames.CONTENT_TYPE, "text/plain; charset=utf-8");
            response.headers().set(HttpHeaderNames.CONTENT_LENGTH, content.readableBytes());

            //将构建好 response返回
            ctx.writeAndFlush(response);

        }
    }
}